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THE PHOTOGRAPHIC NEWS. Vol. XXVII. No. 1285.—April 20, 1883. CONTENTS. PAGE Fig. 2. Fig. 1. eHmsam 241 241 242 213 244 245 245 247 248 252 252 253 254 25G 256 25G A.New Background Ine Causes of Frilling in Gelatine Plates. Muybridge’s New Investigation Dr. Eder’s Recent Experimental Investigations on Gelatino- Bromide By-the-Bye,— About Drapery Photographing the “ Soft Palate.” By Edwin Cocking Hardwich on the Lime Light. By T. E. Hardwich, M.A Securing a Dead Black Surface on Optical Brass Work. By William Forgan Notes manipulating the cords ; a half-circle may even be obtained if necessary, and there is obviously no need to disturb the sitter while the desired modification is being effected. A NEW BACKGROUND. A BACKGROUND that forms the subject of a patent in Austria, and is the design of Herr Luck, has just been described in the Correspondenz by Captain Pizzighelli. Its advantage seems to be that while most photographic backgrounds in general use are flat, this can either be em ployed in that position, or made concave, at the will of the photographer. Concave backgrounds are of course no novelty ; as our readers know very well, repeated instances of their use have been given in these columns, from the hollow ^ half-sphere of Mr. Kurtz, and the alcove of M. Adam-Solomon,* down to the simple arrangement at Mr. Mayall’s Brighton studio,* where an articulated wooden screen is made to do duty for the purpose. We append a sketch of Herr Luck’s background. Fig. 1 THE CAUSES OF FRILLING IN GELATINE PLATES. This may probably sound like such thread-bare subjects as the fading of silver prints or the intensification of gela tine negatives, and be passed over as uninteresting and out of date, for now-a-days few workers are troubled with frilling. Yet frilling does exist, and turns up when and where least expected ; and it is no use blinking the fact that our knowledge of gelatine does not quite lead us to state exactly and precisely what frilling really is, how it arises, when it occurs, or the means necessary to prevent it rather than to cure it. The Photographic Club, which may fairly lay claim to being the most advanced of all the photographic confra ternities (for it is generally at the Club that all the novelties are first brought out), has for some time past carried out a very excellent idea of having a definite subject for discussion each evening. At a very recent meeting the subject that heads this occupied the attention of the members, and brought out some very valuable information, the essence of which may be useful to our general readers. Stated in general terms, there are not one-half the com plaints of frilling that used to arise a year or two ago, for commercial plate-makers have, of course, learned how to steer clear of most of the gelatine difficulties ; but that they have yet something to learn is very evident. It is to be regretted that the term “frilling” seems to be applied indiscriminately to all the phases of surface disturbance of gelatine plates, and arose, perhaps, quite consistently from the then most frequent plague of the puckering or goffering round the edges of plates on development, generally at the raw edges of such plates as had been cut up from large plates (four quarter-plates being frequently cut up from one 8, by 645, and in this sense the term “ frilling ” unquestionably applies correctly. But there are other forms of this disease which have received no generic names. For instance, one of the earliest difficulties attendant upon the use of the softer kinds of gelatine was certainly not frilling as commonly understood, but was, as was described by one speaker, a “ disintegration ” of the substance of the film, and may readily be depicted, if we remind those of our readers who have experimented in the preparation of gelatine emulsions how difficult it has always been to make an emulsion with “ Nelson’s No. 1 Photographic.” Prolonged liquefaction of this particular make has, in our hands, invariably ended in the entire loss of its setting power, We have made Correspondence Proceedings of Societies Talk in the Studio To Correspondents Photographs Registered PAGE Patent Intelligence 250 French Correspondence. By Leon Vidal 251 Artistic Printing. By R. Offord 251 Notes on Photography. By E. Howard Fanner View-Meter and Camera Director. By Thomas H. W. shows the front of the screen, and fig. 2 the back. In fig. 2 the background is set up flat, in fig. 1 it is in its con cave position. The frame-work of the background, which is supported on two feet, a a, consists of a row of wooden supports, b b b b, which above and below are fastened to two flexible steel bands, c c. The cross support, d, which may be turned in a vertical direction upon its pivot, makes the background a flat one when in the position indicated in the sketch (fig. 2). If you desire to make the back ground concave, the cross-piece, d, is shifted from its position and turned, and then the cords, e (fig. 1), are drawn as tightly as may be to give the background the required bend. These cords, e, are, as indicated on fig. 1, fastened to the background both above and below, and passing through rollers,//, are thus easily manipulated. There are convenient hooks at the side of the background frame for receiving the cords, bo that after the necessary concavity has been secured, there is no risk of motion. No doubt such a background would be found useful. It need take up no more room than the ordinary one, and a great variety of changes in the lighting may be effected by • See Pritchard’s “ Photographic Studios of Europe.”